D.C.-area employees say mail is piling up as they are unable to finish their routes.

Letter carriers in the Washington, D.C. area told a local news station they have been forced to end their routes before completing their deliveries so they don’t earn overtime, though U.S. Postal Service officials have disputed the claims.

Anonymous USPS employees this week told WJLA -- an ABC affiliate – that their supervisors have told them to end their days early, causing massive pileups and delays of customers’ mail. The employees said the new rule is being strictly enforced by management and is forcing them off the streets as early as 4:30 p.m.

Dave Partenheimer, a USPS spokesman, denied any such cost-cutting initiative to Government Executive, saying letter carriers are “expected to return in accordance with schedule and daily assigned work load.” Regarding D.C. specifically, Partenheimer said supervisors instructed their letter carriers to return by 6 p.m. due to a snowstorm “regardless of deliveries made” for safety reasons.

“That was a unique situation,” he said, referring to the area’s inclement weather during the week of Feb. 10.

WJLA, however, acquired photos of mail piling up in post offices, displayed text messages from managers telling employees to return by 4:30 p.m. and conducted interviews with D.C. residents who said they have not received mail for six days.

While the Postal Service maintains no national policy to get its letter carriers off the streets before dark, it has made a concerted effort to get employees back by 6 p.m., Partenheimer said. These efforts include reevaluating staffing levels, route structures and start times, and adjusting volume arrival issues arising from processing facilities.

In December, postal employee groups spoke out against workers required to make deliveries after dark, saying the practice puts letter carriers in danger. Tyson Barnette, a part-time USPS employee, was shot and killed while on the job at 7:30 p.m. in November in Maryland. In light of the shooting, the Postal Service inspector general has launched a “series of audits into the delivery of mail after 5 p.m.”